Well mandrel having a casing shield

ABSTRACT

A well mandrel having an internal valve pocket for communication with the interior of the mandrel and the well tubing with at least one port extending outwardly from the valve pocket and a shield positioned between the outer end of the port for protecting a casing from fluid flow through the port. The outer end of the port being spaced internally of the outer periphery of the mandrel, and a passageway extending between the outer end of the port and the shield and in communication with the exterior of the mandrel. The port extending laterally outward and the passageway extending longitudinally along the exterior of the mandrel. The passageway extending on either side of the shield to provide a sufficient area for reducing fluid velocity and concentration of fluid wear on the casing. The longitudinal axis of the port being perpendicular, in a mandrel cross section, to the mandrel radius which extends through the vertical axis of the pocket.

United States Patent [191 I Tausch et al.

[ Apr. 30, 1974 WELL MANDREL HAVING A CASING SHIELD I [73] Assignee: Camco Incorporated, Houston, Tex.

[22] Filed: Jan. 18, 1973 21 Appl. No.: 324,867

[52] US. Cl. .Q 166/242 [51] Int. Cl E2lb 17/14 [58] Field of Search 137/155; 166/214, 224 R,

[56] References Cited UNITED STATES PATENTS 3,101,735 8/1963 Brown 137/155 3,727,684 4/1973 Terra] et al. 166/242 Primary ExaminerGeo. V. Larkin Attorney, Agent, or FirmFulbright & Crooker [57] ABSTRACT A well mandrel having an internal valve pocket for communication with the interior of the mandrel and the well tubing with at least one port extending outwardly from the valve pocket and a shield positioned between the outer end of the port for protecting a casing from fluid flow through the port. The outer end of the port being spaced internally of the outer periphery of the mandrel, and a passageway extending between the outer end of the port and the shield and in communication with the exterior of the mandrel. The port extending laterally outward and the passageway extending longitudinally along the exterior of the mandrel. The passageway extending on either side of the shield to provide a sufficient area for reducing fluid velocity and concentration of fluid'wear on the casing. The longitudinal axis of the port being perpendicular, in a mandrel cross section, to the mandrel radius which extends through the vertical axis of the pocket.

11 Claims, 3 Drawing Figures WELL MANDREL HAVING A CASING SHIELD BACKGROUND or THE INVENTION The use of a well mandrel having a valve'pocket and ports for providing fluidcommunication between a well casing and the well tubing is old as shown in US. Pat.

No. 3,603,393. Mandrels generally include a plurality of ports extending from the valve pocket, but because of cross-sectional space limitations, the mandrel ports will be positioned closely adjacent to the interior wall of the casing when the mandrel is inserted into the casing. Since the mandrel remains in position for prolonged periods of time, often many years, fluid flow through the ports, either from the casing into the tubing or from the tubing into the casing, causes wear and erosion on the interior wall of the casing. In particular, if the fluid flows contains particles such as sand, the erosion on the casing interior may be extensive, and in fact, in time, wear through the casing.

The mandrel of the present invention is directed to providing means for protecting the wall of the casing into which the mandrel is positioned from wear from fluid flow between the casing and the mandrel.

SUMMARY Y the port. A passageway is provided betweenthe outer end of the port and the shield in communication with the exterior of the mandrel to provide fluid flow between the tubing and the casing through the port.

A still further object of the present invention is the provision of extending a plurality of ports laterally outwardly from the valve pocket and providing the passageway longitudinally along the exterior of the mandrel.

In addition, the longitudinal passageway may extend on either side of the shield and is provided with a sufficient length so that the area of the passageway adjacent the casing is sufficient for reducing the fluid velocity adjacent the casing for reducing concentration of fluid against and wear on the casing.

Still a further object of the present invention is the provision of a plurality of ports extending laterally outwardly from opposite sides of the valve pocket and a shield positioned on opposite sides of the valve pocket and spaced between the outer ends of the ports and the casing into which the mandrel is inserted.

A still further object of the present invention is providing the longitudinal axis of the port perpendicular, in a cross section of the mandrel, to the mandrel radius which extendsthrough the vertical axis of the pocket for allowing the shield structure to meet the space and strength requirements of the mandrel.

Other and further objects, features and advantages will be apparent from the following description of the presently preferred embodiment of the invention, given for the purpose of disclosure and taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a fragmentary elevational view, partly in cross section, illustrating the well mandrel of the present invention,

FIG. 2 is a cross-sectional view taken along the line 2-2 of FIG. 1, and

FIG. 3 is a cross-sectional view taken along the line 3-3 of FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawing, the numeral 10 generally indicates the well mandrel of the present invention having suitable means such as threads 12 and 14 at each end for connecting the mandrel 10 into a well tubing (not shown) for lowering the tubing and one or more mandrels 10 into a well casing 16.

The mandrel includes a full opening tubing bore 18 which may be aligned with the well tubing permitting a well tool to freely pass through the mandrel 10. In addition, the mandrel 10 includes a valve pocket housing 22 having an internal tubing valve pocket 24 for receiving a conventional valve or other flow control means which controls the flow between the bore 18 and the casing 16 through ports, which will be more fully described hereinafter, from the valve pocket 24.

As noted from FIG. 1, the outer periphery 11 of the mandrel 10 is positioned closely adjacent the interior wall of the casing 16. In prior art mandrels, ports extending from the valve pocket 24 extended to the outer periphery 11 of the mandrel and adjacent the inner wall of the casing 16. Fluid flow against the casing interior wall causederosion, whether the fluid flow was from the casing to the tubing or from the tubing to the easing. However, in the instance where the mandrel was used to conduct well fluids from the tubing through the pocket 24 and up the casing 16, the erosion would be considerable because of the inclusion of particles such as sand in the well fluid and the direct impingement of the flow out of the ports onto the interior of the casing wall 16.

Referring now to FIGS. 1-3, a port or plurality of ports 30, preferably'on both sides of the valve pocket 24, extend laterally outwardly from the pocket 24. The port or ports 30 includes an outer end 32 which are spaced internally of the outer periphery ll of the mandrel 10 thereby being spaced from the inner wall of the casing 16. A shield 34 is spaced from the outer end 32 of the ports 30 and on both sides of the valve pocket 24 and positioned between the outer end 32 of the ports 30 and the interior wall of the casing 16 on the longitudinal axis of the ports 30 to protect the interior wall of the casing 16. Thus, fluid flow flowing from the tubing through the pocket 24 and ports 30 will impinge on the shields 34 instead of directly engaging and eroding the wall of the casing 16.

A passageway 36 is provided between the outer end 32 of the ports 30 on each side of the valve pocket 24 and a shield 34 and is in communication with the exterior of the mandrel 10 to provide fluid flow between the casing 16 and the interior bore 18 of the mandrel 10. For ease of manufacture, the passages 36 may consist of longitudinally milled slots along the outer periphery 11 of the mandrel 10 and the blast shields 34 are secured across the passageways 36 to the mandrel 10 in alignment with the ports 30. Preferably, the longitudinal passageways 36 extend on either side of the shields 34 from the ports 30 and have a sufficient length to provide an area adjacent the interior walls of the casing 16 greater than the cross-sectional areas of the ports 30 communicating therewith for reducing the fluid velocity of the fluid flow thereby reducing the concentration of fluid against and wear on the casing 16.

It is to be noted that the longitudinal axis of a port 30 is perpendicular, in a cross-sectional plane of the mandrel, to the mandrel radius which extends through the vertical axis of the pocket 24 instead of aligned with a mandrel radius as in the prior art. The present structure, therefore, allows the outer ends 32 of the ports 30 to be spaced internally of the outer periphery 11 of the mandrel without substantially weakening the strength of the mandrel so that the mandrel 10 may operate under the required pressure.

The present invention, therefore, is well adapted to carry out the objects and attain the ends. and advantages mentioned as well as other inherent therein. While a presently preferred embodiment of the invention has been given for the purpose of disclosure, numerous changes in the details of construction and arrangement of parts, may be provided without departing from the spirit of the invention and the scope of the appended claims.

What is claimed is:

l. [n a mandrel for use in a well tubing in which the mandrel has an open bore for communication with the well tubing and includes an internal valve pocket for communication with the mandrel open bore, the improvement comprising,

at least one port extending outwardly from the valve pocket, the outer end of said port being spaced internally of the outer periphery of said mandrel,

a shield positioned on the longitudinal axis of the port but spaced from the outer end of the port, and

a passageway between the outer end of the port and the shield in communication with the exterior of the mandrel.

2. The apparatus of claim 1 wherein the port extends laterally outwardly and the communicating passageway extends longitudinally along the exterior of the mandrel.

3. The apparatus of claim 2 wherein the shield includes opposite sides offset from the axis of the port and wherein the passageway extends past said opposite sides of the shield.

4. The apparatus of claim 3 wherein the passageway includes a cross-sectional area greater than the crosssectional area of the port for reducing concentration of fluid wear on a casing into which the mandrel may be inserted.

5. The apparatus of claim 1 wherein the longitudinal axis of said port is perpendicular in a cross section of the mandrel to the mandrel radius which extends through the vertical axis of the pocket.

6. In a mandrel for use in a well tubing in which the mandrel has an open bore for communication with the well tubing and includes an internal valve receiving pocket for communication with the mandrel open bore, the improvement of means for protecting the wall of a easing into which the mandrel is adapted to be positioned from wear from fluid flow between the casing and the mandrel comprising,

a plurality of ports extending laterally outwardly from the valve pocket, the outer ends of said ports being spaced internally from the outer periphery of said mandrel,

a shield carried by the mandrel positioned on the longitudinal axis of the ports but spaced from the outer ends of said ports whereby said shield is positioned between the ports and the casing into which the mandrel is inserted, and

a longitudinal passageway extending between the outer end of the ports and the shield in communication with the exterior of the mandrel.

7. The apparatus of claim 6 wherein the longitudinal passageway extends on either side of the shield.

8. The apparatus of claim 6 wherein the longitudinal passageway has a cross-sectional area at the mandrel periphery greater than the cross-sectional area of the ports for reducing fluid velocity and concentration of fluid wear on the casing.

9. The apparatus of claim 6 wherein the longitudinal axis of the ports is in a vertical plane that is generally perpendicular in a cross section of the mandrel to the mandrel radius which extends through the vertical axis of the pocket.

10. In a mandrel for use in a well tubing in which the mandrel has an open bore for communication with the well tubing and includes an internal offset valve receiving pocket in communication with the mandrel open bore, the improvement of means for protecting the wall of a casing into which the mandrel is positioned from wear from fluid flow between the casing and the mandrel comprising,

a plurality of ports extending laterally outwardly from opposite sides from the valve pocket, the outer ends of said ports being spaced internally from the outer periphery of said mandrel,

a shield positioned on opposite sides of said valve pocket and spaced between the outer ends of the ports and the casing into which the mandrel is inserted, and

a longitudinal passageway on opposite sides of the valve pocket in the periphery of the exterior of the mandrel and in communication with said ports of said opposite sides.

11. The apparatus of claim 10 wherein each shield includes opposite sides offset from the axis of said ports and wherein the longitudinal passageways extend past said opposite sides of the shield. 

1. In a mandrel for use in a well tubing in which the mandrel has an open bore for communication with the well tubing and includes an internal valve pocket for communication with the mandrel open bore, the improvement comprising, at least one port extending outwardly from the valve pocket, the outer end of said port being spaced internally of the outer periphery of said mandrel, a shield positioned on the longitudinal axis of the port but spaced from the outer end of the port, and a passageway between the outer end of the port and the shield in communication with the exterior of the mandrel.
 2. The apparatus of claim 1 wherein the port extends laterally outwardly and the communicating passageway extends longitudinally along the exterior of the mandrel.
 3. The apparatus of claim 2 wherein the shield includes opposite sides offset from the axis of the port and wherein the passageway extends past said opposite sides of the shield.
 4. The apparatus of claim 3 wherein the passageway includes a cross-sectional area greater than the cross-sectional area of the port for reducing concentration of fluid wear on a casing into which the mandrel may be inserted.
 5. The apparatus of claim 1 wherein the longitudinal axis of said port is perpendicular in a cross section of the mandrel to the mandrel radius which extends through the vertical axis of the pocket.
 6. In a mandrel for use in a well tubing in which the mandrel has an open bore for communication with the well tubing and includes an internal valve receiving pocket for communication with the mandrel open bore, the improvement of means for protecting the wall of a casing into which the mandrel is adapted to be positioned from wear from fluid flow between the casing and the mandrel comprising, a plurality of ports extending laterally outwardly from the valve pocket, the outer ends of said ports being spaced internally from the outer periphery of said mandrel, a shield carried by the mandrel positioned on the longitudinal axis of the ports but spaced from the outer ends of said ports whereby said shield is positioned between the ports and the casing into which the mandrel is inserted, and a longitudinal passageway extending between the outer end of the ports and the shield in communication with the exterior of the mandrel.
 7. The apparatus of claim 6 wherein the longitudinal passageway extends on either side of the shield.
 8. The apparatus of claim 6 wherein the longitudinal passageway has a cross-sectional area at the mandrel periphery greater than the cross-sectional area of the ports for reducing fluid velocity and concentration of fluid wear on the casing.
 9. The apparatus of claim 6 wherein the longitudinal axis of the ports is in a vertical plaNe that is generally perpendicular in a cross section of the mandrel to the mandrel radius which extends through the vertical axis of the pocket.
 10. In a mandrel for use in a well tubing in which the mandrel has an open bore for communication with the well tubing and includes an internal offset valve receiving pocket in communication with the mandrel open bore, the improvement of means for protecting the wall of a casing into which the mandrel is positioned from wear from fluid flow between the casing and the mandrel comprising, a plurality of ports extending laterally outwardly from opposite sides from the valve pocket, the outer ends of said ports being spaced internally from the outer periphery of said mandrel, a shield positioned on opposite sides of said valve pocket and spaced between the outer ends of the ports and the casing into which the mandrel is inserted, and a longitudinal passageway on opposite sides of the valve pocket in the periphery of the exterior of the mandrel and in communication with said ports of said opposite sides.
 11. The apparatus of claim 10 wherein each shield includes opposite sides offset from the axis of said ports and wherein the longitudinal passageways extend past said opposite sides of the shield. 